Jar-wrench.



Y WJ 'TA/ 55555.-

NO. 830,021. PATENTBD SEPT. 4, 1906. S. P. STEVER.

JAR`WRENGH.

APPLICATION FILED SEPT.18, 1905.

UNITED STATES PATENT OFFIOE.

JAR-WRENCH.

Specification of Letters Patent.

Patented sept. 4, 1906.

Application led September 18, 1905. Serial No. 278,940.

To .a/ZZ whom t may concern,.-

Be it known that I, SOLOMON FINK Srnvnn, a citizen of the United States, .residing at Fairfield, in the county of Jefferson and State of Iowa, have invented certain new and useful Improvements in Jar-Vrenches, of which the following is a specification.

My invention relates to a detachable clamp especially adapted for use with the usual preserving-jars, and it consists in the constructions and combinations herein described and claimed.

In the accompanying drawings, formin, a part of this application, and in which simi ar reference-symbols indicate corresponding parts in the several views, Figure l is a perspective view illustrating my improved clamp applied to a jar. Fig. 2 is a view showing my improved clamp; and Fig. Sis a detail view, on an enlarged scale, showing the inner engaging surface of my clamp.

Referring to the drawings, A indicates my improved clamp comprising a curved engaging portion B, provided with a handle C at its respective ends. The engaging portion B is formed on its inner surface with a plurality of relatively small recesses or notches D, which are widely spaced a art, as clearly shown in Fig. 2. At one si e of each notch is a sharp projection or tooth E, having its side adjacent to the notch formed in a plane substantially axial to the curved portion of the clamp and its other side inclined to the curved portion of the clamp. The edge of each notch opposite such tooth is provided with a sharp engaging edge F, which lies substantially at the surface of the curved body portion of the clamp.

It will be seen that by applying my clamp to a jar and exerting pressure on the handles C the short projections E will be forced into the material of the jar sufficiently to bring the curved body portion of the clamp into contact therewith. IVhen a clamp so positioned is turned in the direction of the arrow shown in Fig. 2, any tendency to slip on the jar is resisted by the full strength of the teeth E, since the substantially 4normal faces of the projections constitute the active engaging surfaces during such movement. On the other hand, if the clamp be turned in the opposite direction from that indicated by the arrow in Fig. 2, the tendency of the clamp to slip on the jar will be resisted solely by the sharp engaging edges F, since in such movement the inclined faces of the projections E will be in advance and constitute the active engagingv surfaces of such teeth. It will therefore be obvious upon motion in this direction, that the tendency of the clamp to slip will be resisted entirely by the engagement of the sharp edges F with the material of the jar, and that when the turning force exceeds the resistance exerted by the engagement of these sharp edges the projections E will be forced out of the material of the jar by the wedging action of their inclined faces and the clamp will be free to slip.

From the foregoing description it will be understood that I have produced a clamp provided with two sets of different engaging devices on its clamping-surface, such two sets of engaging devices being constructed, respectively, to engage upon opposite movements of the clamp. It will also be clear that by arranging these two sets of engaging devices in two different concentric planes and by shaping thern as shown neither set will interfere with nor be injured during the operation of the other.

In the operation of my device in screwing down jar-caps the clamp is applied to the cap with the sharp edges F in engaging operation. The cap is then screwed down until the resistance of the sharp edges is overcome and the clamp slips. In such use it will be manifestly impossible to exert an injurious force on the cap. In case it is desired to apply a great deal of force to the jar-ca as where a cap has become corroded in p ace, the clamp is applied with the substantially radial sides of the projections E in engaging operation with the clamp, in which position a force can be exerted sufficient either to break these engaging projections or strip the metal between them.

My improved clamp may be formed of any suitable material; but I prefer to construct it of a single resilient piece.

Having thus fully described my invention, what I claim as new, and desire to secure by Letters Patent, is-

As an article of manufacture, a j ar-wrench comprising a curved body portion provided IOO With a plurality of spaced indentations, a side of each indentation opposite said short short projection extending from the body projection, substantially as described. 1o portion at one side of each indentation, and In testimony whereof I affix my signature formed with its side adjacent the indentation in presence of two Witnesses.

lying in a plane substantially normal to the SOLOMON F. STEVER. Curved body portion, and With its other side Witnesses: inclined to said Curved body portion, and a G. AYERS,

sharp edge formed on the body portion at the CHARLES LOWELL HOWARD. 

